Although certain aminobenzotriazoles have been reported for a wide variety of uses in the prior art, the disclosure of such compounds as dyes for polyester fibers has been relatively limited. Various compounds are reported in the literature, such as Sasse et al, U.S. Pat. No. 2,943,017, who reports certain benzotriazoles as being suitable for fungicidal use. Additional benzotriazoles are reported in patents to Hanhart, U.S. Pat. No. 2,671,775; Scalera, U.S. Pat. No. 2,675,376; Margot et al, U.S. Pat. No. 2,806,035; and Mingasson, U.S. Pat. No. 3,417,075. Various azo derivatives of benzotriazoles are reported where the aminonitrobenzotriazole is diazotized, and then reacted with a coupler. French Pat. No. 1,471,064, reports certain benzotriazoles as dyestuffs; however, such dyestuffs are preferably quaternary compounds which are exemplified as acrylonitrile dyestuffs.
In accordance with the invention there are provided a new class of dyestuffs produced from diazotized 4-amino-7-nitro-benzotriazole, which yield excellent dyeings on polyester fabrics.